This invention relates to equipment and methods for the emergency removal of equipment from offshore oil platforms for fire control purposes and more particularly to equipment and methods for using a service vessel for pulling outer walls and equipment from a platen to provide a clear path to a fire site.
Large quantities of hydrocarbons have been discovered and produced from offshore locations in various parts of the world. Such production provides a substantial part of the total world supply of hydrocarbons and is expected to provide even more in the future. Due to the increasing demand for hydrocarbons, the technology required for finding and producing oil in offshore locations has developed rapidly. Platforms are commonly designed for water depths of 500 feet or more and for hostile environments such as the North Sea. To justify the expense of building platforms in such environments, a large number of wells, for example 50 or more, must be drilled from each platform. As a result, large quantities of equipment must be concentrated around wellhead sites on the platforms and much of the equipment is enclosed in protective modules or rooms surrounding the wellhead sites. The platforms have in essence become large buildings, often five to six stories tall, supported on platform piers or legs, including living quarters and recreational areas for 100 or more workmen in addition to the work areas around the wellheads.
As with any other oil drilling operation, there is always a chance of a blowout or other disaster which can result in explosion, fire, and a loss of great quantities of hydrocarbons in addition to the possible injuries to the operating personnel. The problems of fighting a fire on an offshore oil well are compounded by the fact that the wellheads are totally surrounded by what amounts to a multistory building structure and large quantities of equipment which block access to the fire site. Upon occurrence of a blowout, all power on a platform is shut down to avoid starting a fire. If a fire does begin, it is essentially impossible to maintain power systems due to extensive damage. In any case, the personnel are evacuated from the platform as quickly as possible so that no one would be available to man fire fighting equipment even if power were available. While conventional fire fighting ships can spray water on a burning platform, this does little good unless a clear path to the fire site is provided. Fire fighters must have some type of vessel or platform provided near a burning platform since it is usually too dangerous to attempt to board the platform itself while a well is burning out of control. It can be seen that fire control from an adjacent work platform would be greatly facilitated by some means for providing a clear path to the wellheads. In addition, it can be seen that the clearing of a path to the fire site is preferably done as rapidly as possible and must be done from an adjacent work platform.